Asthmatic responses are induced by environmental oxidants and allergens. A component of the asthmatic response is lung eosinophilia. Eosinophilia with asthma is a risk factor for mortality from chronic obstructive pulmonary disease. Infiltration of eosinophils into the lung in experimental asthma is dependent on the adhesion molecule vascular cell adhesion molecule-1 (VCAM-1) on endothelial cells. We have discovered a signal transduction pathway for VCAM-1. VCAM-1 activates endothelial cell NADPH oxidase production of low levels of reactive oxygen species (ROS). These ROS are required for localized endothelial cell retraction during VCAM- 1-dependent leukocyte migration in vitro. Thus, VCAM-1 is not simply a scaffold for leukocyte migration but activates an endothelial cell 'gate-like' function. We propose to examine VCAM-1-dependent signals in vivo and structure/function analysis of the cytoplasmic domain of VCAM-1. To test whether these VCAM-1 signals function in vivo, VCAM-1-dependent eosinophilia in experimental asthma will be examined. We hypothesize that in experimental asthma, endothelial cell gp91 phox is required for lung eosinophilia. To study the pathogenesis of asthma, we will use a NADPH oxidase deficient model consisting of chimeric mice with wild type leukocytes and gp91 phox deficient nonhematopoietic cells.
In specific aims 1 -2, we will determine whether ovalbumin-challenged chimeric mice exhibit alterations in lung 1) leukocyte infiltration, 2) expression of adhesion molecules, cytokines and chemokines that regulate eosinophilia, and 3) airway hyperresponsiveness. It will be determined whether endothelial cell gp91 phox-mediated changes in the lung inflammation are rescued using transgenic and adoptive cell transfer approaches. To examine the structure/function of the cytoplasmic domain of VCAM-1, VCAM-1 signals will be examined in vitro using wild type and chimeric VCAM-1 molecules. The 13 amino acid cytoplasmic domain of VCAM-1 is identical in mice and humans, suggesting that it has an important function. This domain contains potential phosphorylation sites. We hypothesize that ligand binding to VCAM-1 activates phosphorylation of the VCAM-1 cytoplasmic domain for stimulation of endothelial cell ROS generation and endothelial cell actin restructuring. Biochemical, pharmacologic and genetic approaches will be used to address this hypothesis.
In aim 3, it will be determined whether mutations in serines and tyrosine in the cytoplasmic domain of VCAM-1 alters VCAM-1 activation of NADPH oxidase.
In aim 4, it will be determined whether ligand binding to VCAM-1 activates phosphorylation of serines and tyrosine in the cytoplasmic domain of VCAM-1. The identification of mechanisms for VCAM-1 modulation of lung eosinophilia will provide new insights into regulation of lung eosinophilia as well as provide a basis towards proposing interventions in the VCAM-1-dependent eosinophilia component of asthma.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Research Project (R01)
Project #
5R01HL069428-04
Application #
7382590
Study Section
Lung Cellular, Molecular, and Immunobiology Study Section (LCMI)
Program Officer
Noel, Patricia
Project Start
2005-04-01
Project End
2009-03-31
Budget Start
2008-04-01
Budget End
2009-03-31
Support Year
4
Fiscal Year
2008
Total Cost
$322,145
Indirect Cost
Name
Northwestern University at Chicago
Department
Internal Medicine/Medicine
Type
Schools of Medicine
DUNS #
005436803
City
Chicago
State
IL
Country
United States
Zip Code
60611
Abdala-Valencia, Hiam; Kountz, Timothy S; Marchese, Michelle E et al. (2018) VCAM-1 induces signals that stimulate ZO-1 serine phosphorylation and reduces ZO-1 localization at lung endothelial cell junctions. J Leukoc Biol 104:215-228
Abdala-Valencia, Hiam; Berdnikovs, Sergejs; Cook-Mills, Joan M (2013) Vitamin E isoforms as modulators of lung inflammation. Nutrients 5:4347-63
Berdnikovs, Sergejs; Abdala-Valencia, Hiam; Cook-Mills, Joan M (2013) Endothelial cell PTP1B regulates leukocyte recruitment during allergic inflammation. Am J Physiol Lung Cell Mol Physiol 304:L240-9
Cook-Mills, Joan M (2013) Isoforms of Vitamin E Differentially Regulate PKC ? and Inflammation: A Review. J Clin Cell Immunol 4:
Marchese, Michelle E; Berdnikovs, Sergejs; Cook-Mills, Joan M (2012) Distinct sites within the vascular cell adhesion molecule-1 (VCAM-1) cytoplasmic domain regulate VCAM-1 activation of calcium fluxes versus Rac1 during leukocyte transendothelial migration. Biochemistry 51:8235-46
Cook-Mills, Joan M; Marchese, Michelle E; Abdala-Valencia, Hiam (2011) Vascular cell adhesion molecule-1 expression and signaling during disease: regulation by reactive oxygen species and antioxidants. Antioxid Redox Signal 15:1607-38
Cook-Mills, Joan M; McCary, Christine A (2010) Isoforms of vitamin E differentially regulate inflammation. Endocr Metab Immune Disord Drug Targets 10:348-66
Berdnikovs, Sergejs; Abdala-Valencia, Hiam; McCary, Christine et al. (2009) Isoforms of vitamin E have opposing immunoregulatory functions during inflammation by regulating leukocyte recruitment. J Immunol 182:4395-405
Deem, Tracy L; Abdala-Valencia, Hiam; Cook-Mills, Joan M (2007) VCAM-1 activation of endothelial cell protein tyrosine phosphatase 1B. J Immunol 178:3865-73
Abdala-Valencia, Hiam; Earwood, Julie; Bansal, Shelly et al. (2007) Nonhematopoietic NADPH oxidase regulation of lung eosinophilia and airway hyperresponsiveness in experimentally induced asthma. Am J Physiol Lung Cell Mol Physiol 292:L1111-25